From the 23 minutes of mayhem on June 29 (P.K. Subban/Shea Weber trade, Taylor Hall/Adam Larsson trade, Steven Stamkos re-signing) to some intriguing bargain-bin acquisitions, it was a summer filled with unexpectedness.

It's now January and, as the 2016-17 season approaches the midway point, it feels appropriate to check in on five key off-season moves (all statistics current through Sunday):

Canadiens trade P.K. Subban to Predators for Shea Weber

The blockbuster swap that tore apart the hockey community has aged well for both clubs, although one team has extracted more goodness thus far.

Weber, skating a team-high 25:57 per night for the Habs, is a Norris Trophy favourite armed with 26 points in 40 games. Subban, meanwhile, is on injured reserve nursing a herniated disc following a 17-point, 29-game start to his Nashville tenure.

Hard-shooting Weber, paired with Alexei Emelin, leads NHL defencemen in power play goals (8) and ranks second in total goals (10). The former Preds captain is rocking impressive 5-on-5 numbers, as both his puck-possession (51.2) and goals-for (62.9) percentages are in the black.

Weber and Subban battle comparable opponents, according to Corsica.hockey’s quality of competition metric, but Subban is generating more even-strength offence (1.0 point per 60 minutes vs. Weber’s 0.8/60). The charismatic 27-year-old remains one of the league’s premier possession players (54.3%).

Montreal deserves the slight edge here. The script may flip by season’s end but, overall, it appears to be a win-win situation over the short term.

Check back in 2020, when Weber’s 35 and still eating $8 million in cap space for the next half-decade, and the trade will most certainly be one-sided.

Oilers trade Taylor Hall to Devils for Adam Larsson

In acquiring Larsson, Edmonton attacked a glaring need for structure on the back end. Likewise, Hall’s speed and finesse figured to jar New Jersey’s stagnant offence.

The early returns from the polarizing trade favour the dynamic Hall, who tops all Devils in points (25) despite missing 10 games and drawing Travis Zajac and P.A. Parenteau as first-line mates. Most impressively, when Hall is on the ice at 5-on-5 the team generates 10 more shot attempts per 60 minutes than when he is on the bench.

Larsson, as many predicted, is influencing the Oilers in more subtle ways. The throwback rearguard is enjoying a fine season, playing the bulk of the first half with Oscar Klefbom, but doing so in a supporting role (fourth in ice time among Edmonton ‘D’). The young Swede is issuing three hits and blocking 1.7 shots per game.

This is a difficult trade to analyze because the two teams and the two players involved are so different. However, feel free to suppress any Oilers-related praise — now and over time — because the haul for Hall feels underwhelming (two high draft picks probably would have silenced critics) even if Larsson hits his ceiling as an elite shutdown blueliner.

Wild sign Eric Staal (3 years, $10.5 million)

Staal, the veteran NHL centre who has endured plenty of wear and tear on the body, is defying the odds in the early stages of his Minnesota experience.

With his offensive output on the decline, his age hitting 32 a month into the deal and the $3.5 million in cap room required for his services, the Staal contract did not seem like smart business on July 1.

Six months later, nobody is questioning Chuck Fletcher for the move. The general manager and the rest of us are witnessing a triumphant return to form from Staal, who leads or is tied for the team lead in shots (105), goals (13), game-winning goals (5), assists (22) and points (35).

Blue Jackets sign Sam Gagner (1 yr., $650,000)

From a strictly cost-per-point standpoint, Gagner is the league’s best bargain. Columbus is paying the 27-year-old centre $10,000 for every mark on the scoresheet.

Gagner, who spent seven seasons in Edmonton before a pair of one-year stops in Arizona and Philadelphia, has 14 goals and 30 points in 38 games, setting the table to establish new personal benchmarks.

Nearly half of Gagner’s points (14) are of the power-play variety, which is by design. Coach John Tortorella is saving Gagner’s energy for the man advantage, limiting him to roughly 11 even-strength minutes but sending him over the boards for 2:44 on the PP.

Coyotes select Jakob Chychrun (16th overall)

Arizona general manager John Chayka worked the phones on draft day, trading up for the opportunity to snag Chychrun before another team pounced on a falling stock.

Chychrun, a two-way blueliner who hails from Boca Raton, Fla., is rewarding Chayka, pitching in a tidy seven points and earning a penalty-killing role through his first 31 NHL games.

Just five players from the 2016 draft stuck with their big clubs -- the first, second, fourth and sixth picks, who are all forwards, plus Chychrun. And on Monday, the Oilers' Jesse Puljujarvi was demoted to the AHL.

The jury may still be out on Chychrun’s potential but, at worst, he is destined to carve out a long career as a quality NHL defenceman.

QUICK HITS: PASS OR FAIL?

Islanders sign Andrew Ladd

In its infancy, this contract (7 years, $38.5 million) is an unmitigated disaster. Paid the big bucks to help offset losing Frans Nielsen and Kyle Okposo to free agency, Ladd has 12 points in 38 games.

Pass or fail? Fail (probably for a long time)

Maple Leafs sign Nikita Zaitsev

Zaitsev, 25, has found a home on Toronto’s first defence pairing alongside Morgan Rielly. The smooth-skating rookie is making $1.775 million ($925,000 cap hit) on a one-year deal but is assembling a strong case for a massive raise.

Pass or fail? Pass (with flying colours)

Blue Jackets select Pierre-Luc Dubois

Columbus shockingly passed over super Finn Jesse Puljujarvi to pick power forward Dubois third overall in last summer’s draft. Dubois’ body of work this season — 18 points in 20 QMJHL games and a subpar performance at the world junior championship — falls way short of expectations.